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Since the beginning of time, tuberculosis (TB) has been a fatal illness that predominantly affects the human lungs before spreading to other organs including the brain, spine, etc. The main elements of TB mitigation are age-dependent heterogeneity, identifying those who are latently infected, and treating them using the right diagnostic strategy. In this present work, the complex transmission mechanism of this disease in a population is described by a coupled system of integro-partial differential equations (IDE-PDE). The system's well-posedness requirement is confirmed. The proposed system's basic reproduction number (R 0) is obtained. This work provides a complete analysis of the qualitative properties of the model, including steady state existence, asymptotic smoothness of the solution semi-flow, uniform persistence of the endemic equilibrium, and the global asymptotic stability criterion. It is observed that in assessing the severity of the pandemic, the value of R 0 is crucial. Additionally, the stability results are visually illustrated by solving the model equations numerically while assuming two hypothetical cases. The current work also suggests several methods for reducing the value of the basic reproductive number (R 0) by manipulating a few parameter values, which may help to lessen the prevalence of TB in a community. [ABSTRACT FROM AUTHOR]

Reliable and rapid estimation of blood flow dynamics factors in eccentric stenotic arteries could significantly improve clinical treatments. Numerical simulation methods such as FSI and CFD are widely used to investigate blood flow conditions. However, both FSI and CFD are computationally expensive and not suitable for large-scale research. This work proposes an effective approach for estimating the blood flow dynamics factors of eccentric stenotic arteries based on ML. The estimation approach includes three steps: (a) blood flow conditions of idealized eccentric stenotic arteries modeled with different geometric parameters were simulated by CFD and FSI, and the error between CFD and FSI results were evaluated, (b) datasets of nonlinear relationships between discretized geometric parameters and blood flow dynamics factors were created using CFD, and (c) blood flow dynamics factors of eccentric stenotic arteries were estimated by carefully designed ML model. The accuracy validation was conducted by different representative cases, which have different combinations of geometric parameters including stenosis severity, eccentricity, and stenosis plaque length. The ML model can output the blood flow dynamics factors including peak wall shear stress and peak systole velocity accurately within 1 s, which shows proposed approach not only achieves accurate estimation of blood flow dynamics factors but also bypasses the expensive computational cost. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to perform three-dimensional numerical computations for blood flow through a double stenosed carotid artery. Pulsatile flow with Womersley number (Wo) of 4.65 and Reynolds number (Re) of 425, based on the diameter of normal artery and average velocity of inlet pulse, was considered. Design/methodology/approach: Finite volume method based ANSYS Fluent 20.1 was used for solving the governing equations of three-dimensional, laminar, incompressible and non-Newtonian blood flow. A high-quality grid with sufficient refinement was generated using ICEM CFD 20.1. The time-averaged flow field was captured to investigate the effect of severity and eccentricity on the lumen flow characteristics. Findings: The results show that an increase in interspacing between blockages brings shear layer instability within the region between two blockages. The velocity profile and wall shear stress distribution are found to be majorly influenced by eccentricity. On the other hand, their peak magnitude is found to be primarily influenced by severity. Results have also demonstrated that the presence of eccentricity in stenosis would assist in flow development. Originality/value: Variation in severity and interspacing was considered with a provision of eccentricity equal to 10% of diameter. Eccentricity refers to the offset between the centreline of stenosis and the centreline of normal artery. For the two blockages, severity values of 40% and 60% based on diameter reduction were permuted, giving rise to four combinations. For each combination, three values of interspacing in the multiples of normal artery diameter (D), viz. 4D, 6D and 8D were considered. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to study haemodynamic flow characteristics and entropy analysis in a bifurcated artery system subjected to stenosis, magnetohydrodynamic (MHD) flow and aneurysm conditions. The findings of this study offer significant insights into the intricate interplay encompassing electro-osmosis, MHD flow, microorganisms, Joule heating and the ternary hybrid nanofluid. Design/methodology/approach: The governing equations are first non-dimensionalised, and subsequently, a coordinate transformation is used to regularise the irregular boundaries. The discretisation of the governing equations is accomplished by using the Crank–Nicolson scheme. Furthermore, the tri-diagonal matrix algorithm is applied to solve the resulting matrix arising from the discretisation. Findings: The investigation reveals that the velocity profile experiences enhancement with an increase in the Debye–Hückel parameter, whereas the magnetic field parameter exhibits the opposite effect, reducing the velocity profile. A comparative study demonstrates the velocity distribution in Au-CuO hybrid nanofluid and Au-CuO-GO ternary hybrid nanofluid. The results indicate a notable enhancement in velocity for the ternary hybrid nanofluid compared to the hybrid nanofluids. Moreover, an increase in the Brinkmann number results in an augmentation in entropy generation. Originality/value: This study investigates the flow characteristics and entropy analysis in a bifurcated artery system subjected to stenosis, MHD flow and aneurysm conditions. The governing equations are non-dimensionalised, and a coordinate transformation is applied to regularise the irregular boundaries. The Crank–Nicolson scheme is used to model blood flow in the presence of a ternary hybrid nanofluid (Au-CuO-GO/blood) within the arterial domain. The findings shed light on the complex interactions involving stenosis, MHD flow, aneurysms, Joule heating and the ternary hybrid nanofluid. The results indicate a decrease in the wall shear stress (WSS) profile with increasing stenosis size. The MHD effects are observed to influence the velocity distribution, as the velocity profile exhibits a declining nature with an increase in the Hartmann number. In addition, entropy generation increases with an enhancement in the Brinkmann number. This research contributes to understanding fluid dynamics and heat transfer mechanisms in bifurcated arteries, providing valuable insights for diagnosing and treating cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to determine the impact of two-phase power law nanofluid on a curved arterial blood flow under the presence of ovelapped stenosis. Over the past couple of decades, the percentage of deaths associated with blood vessel diseases has risen sharply to nearly one third of all fatalities. For vascular disease to be stopped in its tracks, it is essential to understand the vascular geometry and blood flow within the artery. In recent scenarios, because of higher thermal properties and the ability to move across stenosis and tumor cells, nanoparticles are becoming a more common and effective approach in treating cardiovascular diseases and cancer cells. Design/methodology/approach: The present mathematical study investigates the blood flow behavior in the overlapped stenosed curved artery with cylinder shape catheter. The induced magnetic field and entropy generation for blood flow in the presence of a heat source, magnetic field and nanoparticle (Fe3O4) have been analyzed numerically. Blood is considered in artery as two-phases: core and plasma region. Power-law fluid has been considered for core region fluid, whereas Newtonian fluid is considered in the plasma region. Strongly implicit Stone's method has been considered to solve the system of nonlinear partial differential equations (PDE's) with 10–6 tolerance error. Findings: The influence of various parameters has been discussed graphically. This study concludes that arterial curvature increases the probability of atherosclerosis deposition, while using an external heating source flow temperature and entropy production. In addition, if the thermal treatment procedure is carried out inside a magnetic field, it will aid in controlling blood flow velocity. Originality/value: The findings of this computational analysis hold great significance for clinical researchers and biologists, as they offer the ability to anticipate the occurrence of endothelial cell injury and plaque accumulation in curved arteries with specific wall shear stress patterns. Consequently, these insights may contribute to the potential alleviation of the severity of these illnesses. Furthermore, the application of nanoparticles and external heat sources in the discipline of blood circulation has potential in the medically healing of illness conditions such as stenosis, cancer cells and muscular discomfort through the usage of beneficial effects. [ABSTRACT FROM AUTHOR]

Stenosis is a tiny plaque-like structure that builds up in the arterial wall owing to the sediment of cholesterol, fats, and pearly substances. Such inward proliferation in arteries significantly inhibits blood flow, which leads to a lack of nutrients and oxygen in the organs. Therefore, exploring the transport characteristics of blood fluid flow in stenosis arteries plays a prominent role in enhancing blood transportation. As a result, the present mathematical model is devoted to scrutinizing the flow of Sutterby gold blood nanofluid in two distinct stenosis arteries with periodic body acceleration. It is observed that the Sutterby rheology model is treated as blood, and the single-phase model is used for exposing the nanofluid behaviour. Dimensional non-linear PDEs of the current model are reduced to the set of dimensionless PDEs with the help of non-similar variables. A finite-difference approach is manipulated to compute the dimensionless PDEs. The physical features of governing flow parameters on the Sutterby nanofluid velocity, temperature, resistance impedance, flow rate, and wall shear stress are exposed through graphs. It is found that the composite stenosis has a lower wall shear stress than the irregular stenosis. Sutterby blood nanofluid velocity is elevated with the rising of nanoparticle volume fraction. When employing a gold nanofluid containing 5% volume fraction, the temperature in the irregular artery rises by 26.004% compared to the base fluid (blood). Similarly, in the composite artery, utilizing the same 5% volume fraction of the gold nanofluid leads to a temperature increase of 32.6207%. The blood flow pattern exhibits a 0.2340% higher in the irregular artery as compared to the composite artery. [ABSTRACT FROM AUTHOR]

In this article, we propose and analyze the robust modified characteristics variational multiscale (MCVMS) method for solving the blood solute dynamics model, which consists of the Navier–Stokes equations to describe the blood flow in the lumen, the advection–diffusion equation for the lumenal concentration and the pure-diffusion equation for the arterial wall concentration, separated by the endothelial layer as interface. This method is based on the combination of the characteristics temporal discretization to deal with the difficulty that arises by the nonlinear terms and the projection-based variational multiscale (VMS) technique to stabilize the spurious oscillation caused by the lower diffusivity of the solute concentration. The natural combination of these methods retains the best features and overcomes their deficits. The global problem is divided into three subproblems, standing on the full explicitly uncoupled VMS stabilization terms, by lagging the projection terms for the velocity and the lumenal concentration onto the previous time level, and the explicit treatment of the interface terms. The unconditional stability and the optimal error estimate are derived rigorously for the newly introduced method. The exclusive feature of the proposed method is demonstrated by performing four numerical experiments, which achieves optimal convergence order and illustrates the flow behavior, solute concentration, wall shear stress, pressure distribution in a curved arterial blood vessel and a 3D stenosis artery. [ABSTRACT FROM AUTHOR]

A novel finite-time complex-valued zeroing neural network (FTCVZNN) for solving time-varying Sylvester equation is proposed and investigated. Asymptotic stability analysis of this network is examined with any general activation function satisfying a condition or with an odd monotonically increasing activation function. So far, finite-time model studies have been investigated for the upper bound time of convergence using a linear activation function with design formula for the derivative of the error or with variations of sign-bi-power activation functions to zeroing neural networks. A function adaptive coefficient for sign-bi-power activation function (FA-CSBP) is introduced and examined for faster convergence. An upper bound on convergence time is derived with the two components in the function adaptive coefficients of sign-bi-power activation function. Numerical simulation results demonstrate that the FTCVZNN with function adaptive coefficient for sign-bi-power activation function is faster than applying a sign-bi-power activation function to the zeroing neural network (ZNN) and the other finite-time complex-valued models for the selected example problems. [ABSTRACT FROM AUTHOR]

In this work, the two-phase mixture model is applied to solve the velocity field, the pressure field and obtain the entropy generation rates in a dual-height plate-fin heatsink. The governing equations were solved using the second-order upwind discretization scheme as well as SIMPLE scheme used in coupling the pressure and velocity fields. The Re , nanoparticle concentration (ψ), secondary fin height (h sf), and fin spacing (d sf) were considered within the ranges of 500-2000, 0%-1%, 5 mm-17.5 mm, and 0.25 mm-0.5 mm, respectively. The results demonstrated that S ˙ t h almost decrease by 30% as h sf increases from 5 mm to 17.5 mm. The increase in h sf escalates S ˙ f r by 308% and 238% at Re numbers of 500 and 2000, respectively. In addition, the escalation of Re from 500 to 2000 increases S ˙ f r by 2125% and 1748% for h sf 5 mm and 17.5 mm, respectively. The fin spacing analysis revealed that the lowest S ˙ t h and highest S ˙ f r belong to d sf =0.5 mm. The lower the d sf the higher the backward flow and mixing flow at the heatsink outlet, thereby delay in flow passage and intensification of S ˙ t h and S ˙ f r. [ABSTRACT FROM AUTHOR]

Detailed and accurate evaluation of blood flow through stenotic arteries is important and can provide better clinical care for patients. Lattice Boltzmann method (LBM) represents an alternative approach to study blood flow and the main goal of this study is to validate its accuracy against traditional CFD methods. The validation was performed for blood flow through complex geometries of coronary arteries, by comparing the results with traditional CFD methods. The good agreement of results demonstrates that LBM can be considered as an efficient alternative that can produce fast results of the same quality as traditional CFD methods. • Validation of lattice Boltzmann method against other traditional CFD methods. • Simulations of blood flow through complex geometries of coronary arteries. • Steady state simulations and pulsatile flow of a cardiac cycle. • Strong correlation between obtained values of velocity and wall shear stress. • Standard deviation error for both analyzed parameters varied in less than 5%. [ABSTRACT FROM AUTHOR]

A study conducted at Bern University Hospital in Switzerland evaluated the hemodynamic performance of arterial and venous cannulae in pediatric extracorporeal membrane oxygenation (ECMO) circuits under pulsatile and non-pulsatile flow conditions. The research found that pulsatile testing conditions led to more physiological testing conditions and are recommended for ECMO testing. The study concluded that under non-pulsatile conditions, the system exhibited overall higher pressures, resulting in higher support to the patient. The findings were published in the journal Artificial Organs and can be accessed online for further information. [Extracted from the article]

AMINA Sciences LLC has been issued a patent for autoimmune mechanical immunomodulation, focusing on therapeutic apheresis to treat underlying immunological disease processes. The patent describes a novel system and methods for therapeutic apheresis that modulate the immune system by returning blood in pulsatile flow to the patient. This innovative approach aims to change the concentration and migration of immune factors in the body, potentially benefiting various disease states involving immune processes. The system is designed to decrease patients' reliance on immunological drugs and improve the efficacy of therapeutic apheresis sessions. [Extracted from the article]

A patent application by Bryan BIHLMAIER from Provo, UT, US, assigned to Becton Dickinson and Company, details a new flush syringe design for maintaining IV catheters. The syringe aims to provide a pulsating flow of fluid to efficiently clear bacteria and prevent infections in catheters. The design utilizes resonance or flexible members to create the pulsating flow, potentially improving flushing efficiency and reducing the impact on clinicians. The patent application outlines various embodiments and mechanisms for achieving the desired pulsatile flow in the syringe. [Extracted from the article]

A case report from Antwerp University Hospital discusses the first diagnosis of severe coarctation of the aorta necessitating percutaneous intervention during pregnancy. The report highlights the risks associated with unrepaired coarctation of the aorta or severe recurrent stenosis during pregnancy, emphasizing the importance of early diagnosis and intervention. The study underscores the need for a multidisciplinary pregnancy heart team for optimal treatment management in high-risk patients. [Extracted from the article]

Roche Diagnostics Hematology Inc. has been issued a patent for automated systems and methods for preparing biological specimens for examination. The patent covers a device that can process various biological samples, including blood, bone marrow, and other body fluids, by fixing, staining, rinsing, and agitating the specimens. This system aims to provide rapid, efficient, and uniform specimen processing using minimal fluid quantities, making it suitable for preparing and examining biological specimens in healthcare settings. [Extracted from the article]

A patent has been issued for the reprocessing of a physiological sensor by Masimo Corporation, focusing on the replacement of sensing components to improve reliability. The patent aims to address the challenges of reusing sensors in hospitals by replacing worn components while retaining the sensor cable and monitor attachments. This innovation allows for cost savings in refurbishing sensors while maintaining performance standards for physiological monitoring. [Extracted from the article]

A study conducted at New York University (NYU) Langone Health examined the use of an intra-aortic balloon pump (IABP) to generate pulsatile flow during heart transplantation surgeries. The research found that patients who received IABP-generated pulsatile flow experienced shorter organ ischemia times and cardiopulmonary bypass (CPB) times compared to those who did not. The study suggests that maintaining counterpulsation to generate pulsatile flow during CPB may improve end-organ perfusion in heart transplant patients, as indicated by lower postoperative lactate levels. [Extracted from the article]

Researchers at Antwerp University Hospital reported a case of severe coarctation of the aorta in a pregnant woman, highlighting the risks and complications associated with this condition. The patient underwent percutaneous intervention during pregnancy, resulting in successful treatment and a healthy birth. The study emphasizes the importance of considering coarctation of the aorta in young patients with hypertension and the necessity of a multidisciplinary approach for optimal management in high-risk cases. [Extracted from the article]

The US Patent and Trademark Office has published a patent application for an implantable pump system designed to assist patients with end-stage heart failure. The current treatment options for this condition are limited, with cardiac transplantation being the most common but often unavailable due to a shortage of donor hearts. Mechanical implants, such as left ventricular assist devices (LVADs), are an alternative but have their own limitations. The patent application describes a new pump system that aims to address these drawbacks by utilizing an undulating membrane to produce physiological flow rates with low shear forces, allowing for pulsatile flow and reducing the risk of complications. [Extracted from the article]

A new report from Technical and Vocational University (TVU) discusses the impacts of aneurysm deformation induced by a stent on the hemodynamics of blood flow in saccular internal carotid artery aneurysms. The study investigates the role of stents in reducing the risk of aneurysm rupture and hemorrhage. Using computational modeling techniques, the researchers found that stent-induced deformation of the aneurysm reduces blood flow rate and wall shear stress, potentially lowering recurrence rates. However, stenting may also have negative impacts on hemodynamic alterations. This research provides valuable insights into the evaluation and treatment of aneurysms. [Extracted from the article]

Researchers at the University of Saskatchewan have developed a novel centrifugal microfluidic approach for separating circulating tumor cells (CTCs) from healthy cells in the bloodstream. CTCs are important for cancer diagnosis, prognosis, and therapy, but isolating them is challenging due to their low numbers and diverse characteristics. The microfluidic device uses inertial and magnetic forces to sort and capture CTCs based on their size and shape. The device demonstrated high separation efficiency (93%) and has the potential to be a valuable tool for CTC separation. [Extracted from the article]

A study conducted at the University of Rochester in New York examined the reliability of noninvasive blood pressure monitoring in patients with left ventricular assist devices (LVAD) during noncardiac surgeries. The researchers found that monitoring gaps of 10 minutes or longer were more common in patients with the HeartMate 2 LVAD compared to those with the HeartMate 3 LVAD. Morbid obesity and longer surgical duration were also associated with increased monitoring gaps. The findings suggest that anesthesiologists should consider the appropriateness of noninvasive blood pressure monitoring in LVAD patients undergoing noncardiac surgeries. [Extracted from the article]

A patent has been issued to inventors Steven C. Christian and Theodore A. Johnson for a system and method for providing irrigation fluid during cardiac ablation procedures. The patent, assigned to St. Jude Medical, describes a system that delivers irrigation fluid at different flow rates and controls the delivery of power during the procedure. The invention aims to improve temperature monitoring and control, reduce heat transfer between thermal sensors, and enhance the correlation between electrode and tissue interface temperatures. Additionally, the system includes a mechanism for irrigating the ablation electrode assemblies with biocompatible fluids to prevent charring and the formation of coagulum. The patent discusses a system for delivering irrigation fluid during cardiac ablation procedures. Pulsatile flow of irrigation fluid can prevent stagnation areas and improve temperature correlation between the ablation electrode and targeted tissue. The system includes a catheter shaft, an electrode assembly, thermal sensors, an electronic control unit, and a control system for delivering irrigation fluid at different flow rates. The method involves delivering pulsatile flow of irrigation fluid and ablation energy at different power levels based on temperature measurements. The patent aims to improve the effectiveness and safety of catheter ablation procedures for treating arrhythmias. [Extracted from the article]

A clinical trial, NCT06608485, is underway to evaluate the safety and effectiveness of the HARMONIC 700 Shears device in pediatric and adult surgical procedures. The trial aims to collect clinical data and assess the device's ability to achieve hemostasis during vessel transections. It will enroll 165 participants, including both pediatric and adult patients undergoing elective procedures. The trial is not yet recruiting participants and is expected to be completed by July 2026. [Extracted from the article]

A recent study conducted at the Islamia University of Bahawalpur in Pakistan focused on the numerical simulation of pulsatile flow in a curved artery with electro-osmotic effects. The researchers used a theoretical model of tangent hyperbolic fluid and considered the impact of the blood vessel wall. They employed an explicit finite difference method to solve the resulting nonlinear system of differential equations and examined various flow variables. The study found that an increase in flow rate and blood velocity led to a rise in response, while an increase in stenosis height, Weissenberg number, and power-law exponent led to a reverse response. The temperature field was significantly affected by the Brinkman number and the Prandtl number. [Extracted from the article]

410 Medical Inc. has been granted a patent for a system and method that reduces fluid pressure in a fluid line. The invention aims to improve flow rates and reduce user input force when delivering fluid to patients, especially when the source of pressurized fluid has a pulsatile pressure profile. The system includes a tube portion, a source of pressurized fluid, and a fluid pressure regulating device. This device allows for fluid to be delivered to the patient with a pulsatile flow rate, reducing the risk of hemolysis and improving the average flow rate. The patent was filed in December 2020 and published online in September 2024. [Extracted from the article]

Researchers at George Washington University have conducted a study on carotid artery bifurcation models to better understand the internal vortical structures that impact plaque formation. The study found that the main vortex's time of formation is primarily dictated by the artery's geometry, while its lifespan is determined by flow conditions. The research concluded that a high internal carotid artery mass flow rate and a higher favorable pressure gradient maximum magnitude near peak systole are strong indicators of a high predisposition towards atherogenesis. This study provides valuable insights into the factors that contribute to carotid artery atherosclerosis. [Extracted from the article]

A patent has been issued to Edwards Lifesciences Corporation for a system and method for implanting and securing a bioprosthetic device to wet tissue. The patent addresses the challenges associated with securing bioprosthetic heart valves within the tissue annulus and preventing complications such as perivalvular leakage. The invention involves applying a curable composition to the implant device and/or anatomical feature, which can be cured to provide secure adhesion. The patent also includes a kit comprising a bioprosthetic heart valve, a cartridge with a photoinitiator and pre-polymer, and an applicator for delivering the curable composition to the desired location. [Extracted from the article]

A patent application titled "Generating Artificial Pulse" has been published online by the US Patent and Trademark Office. The application, filed by inventor Kevin Bourque, describes a method for operating a continuous flow blood pump to provide pulsatile blood flow. The pump can be modulated to imitate the rate of pressure change of a natural physiologic pulse. The patent application also includes details of a mechanical circulatory assist system comprising a blood pump and a controller that operates the pump in an artificial pulse mode synchronized with the relaxations of the left ventricle. [Extracted from the article]

A recent study from Columbia University provides new information about personalized medicine in the field of cardiology. The study focuses on the advancements in Left Ventricular Assist Device (LVAD) therapy, particularly the HeartMate 3 (HM3) LVAD, which has improved survival rates and quality of life for patients with advanced heart failure. The study discusses the dual role of LVADs as a bridge-to-transplantation and destination therapy, as well as the challenges and complications associated with LVADs. It also highlights emerging strategies for predicting outcomes and potential new technologies and therapies in LVAD management. The study concludes optimistically, suggesting that ongoing research and future innovations have the potential to revolutionize heart failure management and personalize treatment. [Extracted from the article]

The article reports that a patent application titled "Systems And Methods For Simulating Cardiovascular Fluid Flow" was published online on August 22, 2024. Topics discussed include the use of simulation systems for medical training, testing new medical devices, and connecting these systems to flow paths in cadavers or organs.

This article discusses a study on the impact of channel geometry and flow regime on the orientation and morphology of endothelial cells (ECs) in vessel-on-chip (VoC) models. The study compares rectangular cross-section channels, which are commonly used in organ-on-chip models, with tubular channels that have a circular cross-section. The research shows that ECs in tubular channels exhibit more uniform coverage and alignment compared to rectangular channels. The study also examines the adhesive interactions between monocytes and ECs and how EC orientation induced by different flow regimes affects monocyte rolling velocities. The findings highlight the importance of considering both channel geometry and flow conditions in VoC models to improve the accuracy and functionality of biomedical research and personalized medicine. [Extracted from the article]

A recent study conducted at the University of Washington in Seattle explored the biological basis behind the treatment outcomes of cerebral aneurysms using flow diverting stents (FDS). The researchers created patient-specific 3D models of aneurysms and used computational fluid dynamics to analyze the impact of FDS on hemodynamic flow. They found significant changes in gene transcription in endothelial cells (ECs) after FDS placement, particularly related to aneurysm hemodynamics. Further investigation is needed to understand the relationship between these transcriptional changes and treatment outcomes. This research provides valuable insights into the potential mechanisms underlying the effectiveness of FDS in treating cerebral aneurysms. [Extracted from the article]

A mechanical heart valve, an essential prosthetic for managing valvular heart disease, consists of a metal frame housing two or three leaflets (depending on the design) that control blood flow within the heart. However, leaflet dysfunction can impede their movement, leading to valve defects. This study extensively investigates the hemodynamics of such a bileaflet mechanical heart valve with dysfunctions of various extents with the help of direct numerical simulations (DNS) under both steady inflow and pulsatile flow conditions. The results are presented and discussed in terms of spatial variations of velocity magnitude, Reynolds stresses, and surface and time-averaged clinically important parameters such as wall shear stress (WSS), pressure drop, and blood damage. Under steady inflow conditions, the flow field becomes unsteady and turbulent even at a modest Reynolds number of 750 when the valve has 50% defective conditions, in contrast to a steady and laminar flow for a fully functional heart valve with 0% defect condition. The values of WSS also increase by around 50%, and net pressure drops by more than 200% with these defective conditions, which further increase as the defective condition increases. On the other hand, the same trend is also seen under pulsatile flow conditions, with maximum values of wall shear stress and blood damage seen during the peak systolic stage of the cardiac cycle, increasing by more than 200% as the defect condition increases from 0% to 50% for the latter parameter. Furthermore, the present study also investigates the effect of blood rheological behaviors such as shear-thinning and yield stress on hemodynamics past this dysfunctional heart valve. It is seen that blood rheological behavior has a substantial influence on hemodynamics at low Reynolds numbers, diminishing as the Reynolds number increases. Under pulsatile flow conditions, blood exhibiting non-Newtonian characteristics such as shear-thinning shows higher values of wall shear stress and blood damage values compared to Newtonian ones. Therefore, the present study highlights the importance of accounting for blood rheology in clinical assessments. However, this study simulates the cases where both valve leaflets are fixed in position, thereby excluding fluid–structure interaction (FSI) from the present simulations. Such conditions are representative of common occurrences in dysfunctional heart valves. All in all, the in-depth analysis and information obtained from this study are expected to facilitate early detection of valve leaflet dysfunction, thereby contributing to improved clinical management of patients with valvular heart disease. [ABSTRACT FROM AUTHOR]

A patent application for a device that filters embolic material in a vascular system has been made available online. The device aims to prevent particulate matter, such as blood clots or thrombi, from causing damage to bodily tissues. It includes an embolic protection device with a support frame and a filter member, as well as a connector mechanism and a catheter or sheath for delivery. The device is designed to provide increased flexibility, cost-effectiveness, and patient safety during intravascular procedures. [Extracted from the article]

A recent study conducted by researchers at the University of Birmingham in the United Kingdom has developed a mechanical testing system to assess the performance of hemodialysis catheters. Hemodialysis is a treatment for decreased kidney function that involves inserting a catheter into the heart's Right Atrium (RA). The researchers used a computer-aided design (CAD) model of a heart to create a platform that accurately replicates atrial hemodynamic conditions. The study found that the developed system was able to evaluate the performance of two catheters, demonstrating its potential to enhance the development of medical devices in the future. [Extracted from the article]

Researchers at the University of Canterbury in Christchurch, New Zealand have conducted a study on the hemodynamics of the kissing stent (KS) method used to treat aorto-iliac occlusive disease (AIOD). The study used an in vitro model to investigate the effects of the KS configuration on blood flow proximal and distal to the stents. The results showed that while systolic flow appeared normal, there was a collapse of the arterial wall in early diastole, potentially leading to disturbed flow patterns and reduced long-term patency. The findings provide insight into the behavior of stented arteries and may help identify high-risk regions that require closer monitoring. [Extracted from the article]

Researchers from Isfahan University of Technology in Iran have proposed a general scaling law that describes the optimal relationship between bifurcations and pulsatile flow in the vascular system. The scaling law takes into account deviations from Murray's law, which is based on steady-state blood flow, and is more accurate for larger vessels such as the aorta and coronary arteries. The law suggests optimal flow and less flow resistance for the entire range of the vascular system, and the suggested diameter ratios align with clinical morphometric data. Numerical simulations show that the general scaling law provides more efficiency than Murray's law in pulsatile flow. [Extracted from the article]

A recent study conducted at Harbin University in China explored the effects of aortic dissection on blood flow behavior. The researchers used a combination of numerical simulation and in vitro experiments to examine the impact of different tear states on the complex blood flow within abdominal aneurysms. The study found that arterial dissection rupture can lead to increased pressure, reflux, and malperfusion, which can contribute to the development of aortic aneurysms. These findings provide valuable insights into the haemodynamic mechanisms involved in aortic dissection and may inform future clinical trials and simulations. [Extracted from the article]

Researchers from New York University NYU Langone Orthopedic Hospital have discussed the challenges and potential benefits of generating pulsatile flow using clinical continuous flow pumps in the field of cardiovascular physiological phenomena. The use of mechanical circulatory support devices for long-term augmentation of cardiopulmonary function has led to issues such as pump thrombosis and failure, inadequate ventricular unloading, and end-organ hypoperfusion. The researchers propose that modifying continuous flow devices to provide pulsatility could mitigate these risks, but effective implementation has not yet been demonstrated. The study concludes that new pulsatile pumps are needed to achieve adequate physiologic pulsatility with improved side-effect profiles. [Extracted from the article]

The present study examines flow through Bi-Leaflet Mechanical Heart Valves (BMHV) at physiological conditions considering both Newtonian and non-Newtonian fluid models for blood rheology. It is well known that the non-Newtonian effects of blood are pronounced in small diameter arteries. Most of the earlier works on Mechanical Heart Valves (MHV) have considered blood as a Newtonian fluid as the flow involves large-diameter artery such as the aorta. In this work, we have reported the predicted parameters, such as leaflet kinematics, vortex structures, wall shear stress, and blood damage index for both blood models. It is found that the leaflet attributes smaller asynchronous motion in the case of non-Newtonian Carreau fluid model with slightly reduced angular velocity compared to the Newtonian assumption. Predictions on the blood damage index suggest a 21% higher damage while using non-Newtonian model than Newtonian model, which may be attributed to higher levels of mechanical stress within the fluid. However, vortex structures, time-averaged wall shear stress (TAWSS), and oscillatory shear index (OSI) are found to be similar in predictions using both the fluid models. We have used an in-house sharp interface immersed boundary method with fluid–structure interaction to simulate the coupled action of moving valves and pulsatile blood flow. Our findings suggest that the general consensus of using Newtonian model in large arteries may not be appropriate for prediction of leaflet kinematics and blood damage index in Mechanical heart valves. • Newtonian and non-Newtonian blood flow through BMHV is studied. • Carreau model suggests a reduced asynchronous leaflet motion and angular velocity. • Qualitative features indicate more stable flow structures for Carreau model. • Elevated blood damage by 21% is predicted by Carreau model. • Hemodynamic parameters- TAWSS, OSI, and RRT are similar in range for both the models. [ABSTRACT FROM AUTHOR]

A 25-year-old woman experienced intense and pulsatile headaches while being treated with desmopressin for central diabetes insipidus. She initially presented with symptoms of polyuria, polydipsia, intense headache, and visual disturbances. After being diagnosed with CID, she began treatment with desmopressin but was lost to follow-up. When she returned to the hospital 22 months later, she was admitted for evaluation of persistent daily headaches. Her desmopressin dosage was reduced, and she had a positive response, although the outcome is not specified. [Extracted from the article]

A recent study conducted by researchers at Concordia University in Montreal, Canada, explored the role of fluid flow patterns in microbubble-mediated endothelial cell membrane permeabilization. The researchers investigated the response of endothelial cells to ultrasound-stimulated microbubbles under different blood flow conditions. They found that cells cultured under pulsatile flow showed an increase in permeabilized endothelial cells compared to static conditions. Additionally, endothelial permeability was significantly enhanced under pulsatile flow compared to laminar flow. The study highlights the influence of local blood flow dynamics on ultrasound-mediated cell permeabilization. [Extracted from the article]

A patent has been issued for a linear cardiac assist pulsatile pump developed by SummaCor Inc. The pump is designed to assist with circulating blood within the body of a patient, avoiding or minimizing damage to red blood cells. It utilizes a linear reciprocating movement to generate a pulsatile pumping cycle that is compatible with the operation of the patient's heart. The pump can be placed in various locations within the body, such as the ventricles, aorta, or vena cava. It includes an expandable housing, a valve member, and an actuator to generate the pumping cycle. The patent provides detailed descriptions and claims for the design and components of the pump. [Extracted from the article]

A patent has been issued to the California Institute of Technology for a system designed to control vascular wave dynamics and enhance blood flow. The system includes an inelastic member and a pinching member that can be implanted along the aorta. The pinching member is equipped with an actuator and control unit to compress the aorta and generate artificial reflected waves, which can reduce cardiac load and improve blood flow to various organs. The system has the potential to optimize wave reflection and improve the efficiency of the cardiovascular system. [Extracted from the article]

A recent study conducted at the University Center has provided new insights into the hemodynamic pulsatile flow dynamics in carotid artery stenosis. The researchers used advanced computational fluid dynamics simulations to analyze the effects of stenosis on blood flow characteristics and plaque deposition. They found significant differences in hemodynamic characteristics between stenosed and normal arteries, particularly near systolic peaks. These findings contribute to our understanding of cardiovascular disease pathogenesis and provide valuable insights into the hemodynamic effects of arterial stenosis. [Extracted from the article]

Researchers from the National Autonomous University of Mexico (UNAM) have published a study on the electro-osmotic flow of blood with varying cholesterol levels. The study aimed to simulate arterial occlusion and analyze the fluid's rheology using a multi-modal convected Maxwell model equation. The researchers derived analytical solutions using the Fourier transform formalism and validated their predictions with experimental data. This study contributes significantly to the field as there is limited research on electro-osmotic flow in blood with pathologies associated with low and high cholesterol. [Extracted from the article]

This article discusses a study that aims to establish a connection between blood shear forces during valve closure and the likelihood of blood clotting in prosthetic valves. The researchers used pulsatile and quasi-steady flow systems to test different valve designs and measure flow velocity and shear. The results guided the optimization of valve prototypes with reduced thrombogenic potential. The study highlights the importance of considering leaflet geometry and flow velocity in prosthetic valve design to minimize the risk of blood clotting. However, it is important to note that this preprint has not yet undergone peer review. [Extracted from the article]

CorWave SA has developed an implantable pump system to assist patients with end-stage heart failure. This system aims to improve upon previous left ventricular assist devices (LVADs) by addressing issues such as bulkiness, high energy requirements, and the risk of hemolysis. The new system utilizes an undulating membrane to create pulsatile flow similar to that of a natural heart, while maintaining physiological pressure gradients. This innovation has the potential to prolong the lives of patients with end-stage heart failure and improve their quality of life. The system includes an implantable pump, a controller, and a rechargeable battery, and it can be programmed to mimic physiologic flow rates and pulsatility. [Extracted from the article]

A report from the University Medical Centre Groningen in the Netherlands discusses the surgical techniques and clinical implications of bilateral bidirectional cavopulmonary connection in pediatric patients. The presence of bilateral superior caval veins (bSCVs) can negatively impact the outcome of Fontan patients, potentially affecting the eligibility for Fontan completion and increasing the risk of thrombotic complications. Alternative surgical techniques, such as the V- or Y-shape, have shown promising short-term results, but their long-term effects are not yet known. The use of computational fluid simulation to identify the most favorable surgical technique on an individualized basis is also explored. The research suggests that an individualized approach could potentially improve clinical outcomes. [Extracted from the article]